System for locating implantable medical device

Details System for locating implantable medical device System for locating implantable medical device

1999-01-29

2001-10-23

Lacyk, John P. (Department: 3736)

Surgery

Miscellaneous

Devices placed entirely within body and means used therewith

C600S424000

Reexamination Certificate

active

06305381

ABSTRACT:

FIELD OF THE INVENTION
The present invention relates to implantable medical devices and, particularly, to an implantable medical device system for locating an implantable medical device with a high degree of precision.
BACKGROUND OF THE INVENTION
Many implantable medical devices require percutaneous communication. That is, in particular regard to implantable drug infusion devices, such devices often require the drug supply to be replenished. Typically, such replenishment is accomplished by inserting a needle through the skin and into the septum of a drug reservoir in such a device.
Because such a device is implanted and thus not able to be directly seen, care must be taken to ensure that the needle is properly placed into the device before injection. If the needle misses the device and, in particular, misses the drug reservoir in the device, the drugs will be immediately dispensed in the body, having potentially dire consequences for the patient. Moreover, if the needle is not fully placed through the septum and into the drug reservoir, the drug reservoir will not be adequately filled, also having potentially dire consequences for the patient.
Previous attempts have been made to accurately locate and identify implanted devices and, in particular, septum loading to the drug reservoir of implantable drug infusion devices. For example, Celcontrol, Inc. advertised an implantable vascular access device which required the attachment of an electrode to the skin and the attachment of a wire to the hypodermic needle to create a circuit for locating the implantable device. Such a system, besides having more complexity than desired, did not provide an accurate location of the needle in relation to the device without first inserting the needle through the skin. U.S. Pat. No. 5,171,228 disclosed a further system which required an RF transmitter and a transmitting antenna. Such a system, to date, has not proven practical or provided an acceptable precision for locating the implantable device. Thus, there exists a need for a simple device and technique for sensing the position of an implanted device and, in particular, of a drug reservoir septum, without first requiring the skin to be punctured or additional electrode attachments to be made to the patient.
SUMMARY OF THE INVENTION
These and other objects are accomplished by the present invention which includes a system and method for locating an implantable medical device. The system consists of a flat “pancake” antenna coil positioned concentric with the implantable medical device target, e.g. the drug reservoir septum. The system further features a three location antenna array which is separate from the implantable device and external to the patient. The antenna array features three or more separate antennas which are used to sense the energy emitted from the implanted antenna coil. The system further features a processor to process the energy ducted by the antenna array. The system senses the proximity to the implant coil and, thus, the implant device by determining when an equal amount of energy is present in each of the antennas of the antenna array and if each such ducted energy is greater than a predetermined minimum. When such a condition is met, the antenna array is aligned with the implant coil. Thus the needle port through the antenna array is lined up with the septum of the drug reservoir. Alternative embodiments are further disclosed in which the processor and antenna array are positioned within the implanted device while the coil is external to the patient.


REFERENCES:
patent: 4441498 (1984-04-01), Nordling
patent: 4542532 (1985-09-01), McQuilkin
patent: 4757816 (1988-07-01), Ryan et al.
patent: 4760837 (1988-08-01), Petit
patent: 5006115 (1991-04-01), McDonald
patent: 5009644 (1991-04-01), McDonald
patent: 5099845 (1992-03-01), Besz et al.
patent: 5171228 (1992-12-01), McDonald
patent: 6009878 (2000-01-01), Weijand et al.

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